Clutch Failure at the Track w/ pics

[quiksilver55]

So, I was at my local track last friday (Nola Motorsports Park) and experienced my first mechanical failure in the NSX. As I went to downshift into second, I noticed the car wouldn't shift into gear and the pedal did not rebound to it's neutral position. A few attempts proved the same results, so I pulled to the side and was towed off to the track's speed shop.

Doing some research, I thought (hoped) the issue was related to the clutch slave cylinder, but today I got some bad news from the track. After opening the inspection port (?) they found 2 washers and a bent peice of metal that were loose in the housing. Supposedly, this caused the binding in the clutch pedal, etc. Here's a picture of the parts they removed:



The clutch had been replaced by the previous owner 35K miles ago through Basch at the same time the snap ring transmission was replaced. All other clutch components were done as well (master/slave).

Assuming the clutch being replaced is a stock twin disc (I have a '91), I'm looking for recomendations. I will be moving to the SF Bay area this summer and expect to be doing a lot more street driving than I currently do in New Orleans (mostly track time right now). I'd like to have a clutch that is streetable but can endure the track. I have no high horsepower upgrades, but would like to leave some room for options down the road.

I'm all ears! Single disc or twin? Carbon or metallic?

 

[cantdrive55]

I currently have a clutchmasters 6 puck and i really like it. It does have some pretty loud clutch chatter in first and it is a pain to drive in traffic due to the pedal pressure but it doesn't bother me that much. It engages really hard which i like. My car is turbo'd and it holds power great. I have 3 track days on it and im pretty hard on it plus about 15XXX miles of street driving. Ive heard good things about the SOS twin disc.

 

[TyraNSX]

This has been discussed to death multiple times. If you use the search and/or check SoS's website there are a few options.

 

[nsxtasy]

I always liked the stock clutch. I've driven some aftermarket clutches and they were really unpleasant to drive, with hard pedal pressure needed, and a very narrow sweet spot (engagement range), more of an on-off feel to them. I've heard that SoS now has a clutch which is more user-friendly, and is sometimes praised as "as easy to use as the stock clutch", which tells you something about the stock clutch. If you consider going with something other than stock, you might ask around and see if someone nearby who already has one will let you drive his car, so you can "try before you buy".

Incidentally, with 35K miles on your blown clutch, it may have been ready to go anyway. Or, it may not. You'll know for sure when they replace it; they can tell you how much friction material was left.

 

[kookoo4nsx]

I have the SOS Sport 6 puck. A bitch to drive the first 50 miles but it broke in well and now shifts great. Holds 400rwhp nicely. Zero chatter!!!

 

[ryneen]

+1 for the stock clutch. I had 84,000 miles and over 80 track days on my original stock clutch. I wasn't sure when it was going to wear out so I replaced it at 84,000 miles as preventative maintenance. Ironically, it still had life in it when I took it out. After looking at all the clutch options, I replaced it with another stock factory clutch which now has 30,000 miles on it with a lot of track miles. It is such an easy clutch to drive and is very durable. My wife can easily drive the car. I highly recommend it.

I always liked the stock clutch. I've driven some aftermarket clutches and they were really unpleasant to drive, with hard pedal pressure needed, and a very narrow sweet spot (engagement range), more of an on-off feel to them. I've heard that SoS now has a clutch which is more user-friendly, and is sometimes praised as "as easy to use as the stock clutch", which tells you something about the stock clutch. If you consider going with something other than stock, you might ask around and see if someone nearby who already has one will let you drive his car, so you can "try before you buy".

Incidentally, with 35K miles on your blown clutch, it may have been ready to go anyway. Or, it may not. You'll know for sure when they replace it; they can tell you how much friction material was left.

 

[DDozier]

I have the SOS Sport 6 puck. A bitch to drive the first 50 miles but it broke in well and now shifts great. Holds 400rwhp nicely. Zero chatter!!!

This is a great option for those in the 400+whp club, the amount of effort to opperate this clutch is so simmilar to stock that most will not be able to tell. The issues I have with it is a little bit of chatter on takeup if you do not get the timing perfect, and at the track once warm this clutch is very grabby and will chatter in first gear all the time. If your power goals are going to be under 400whp (it is for most) then get the SOS Sport Clutch with the full face disk. It is as close to stock in feel that you can get and has a little more holding power so you can grow into it. All the Sport clutches have a lighter flywheel and will free up a few HP and help the engine rev from low RPMs quicker.

Dave

 

[quiksilver55]

Well guys, thanks for the info. I spoke with SoS and decided to go with the Sport 350 clutch. This will allow for upgrades down the road while still maintaining street driveability. I have some intentions to supercharge, but not just yet.